Monoazo compounds from 3-aminobenzisothiazoles and substituted α-naphthylamine couplers

ABSTRACT

Monoazo compounds produce fast blue to green shades on polyester, nylon and cellulose acetate fibers and consist of a 2,1-benzisothiazole-3-yl diazo component and an α-naphthylamine coupling component, the nitrogen atom of which is monosubstituted with a cycloalkyl, aryl or substituted alkyl group.

This invention concerns novel azo compounds consisting of certain benzisothiazole diazo components and α-naphthylamine coupling components. This invention also concerns synthetic polyamide fibers dyed with the novel azo compounds.

Our novel azo compounds have the general formula ##SPC1##

Wherein

R¹ and R² each is hydrogen, lower alkyl, lower alkoxy, chlorine or bromine;

R³ is cyclohexyl; lower alkyl cyclohexyl; aryl; alkyl of one to about six carbon atoms substituted with hydroxy, lower alkoxy, lower cyanoalkoxy, lower hydroxyalkoxy, cyano, halogen, aryl, aryloxy, cyclohexyl, lower alkylcyclohexyl, hydroxymethylcyclohexyl, R⁶ --CONHCH₂ --cyclohexyl, R⁷ OOCNHCH₂ -cyclohexyl, R⁷ SO₂ N(R⁸)CH₂ -cyclohexyl, pyrrolidinono, lower alkylpyrrolidinono, phthalimidino, --N(R⁸)CO--R⁶, --NHCOO--R⁷, --N(R⁸)SO₂ R⁷, --OOC--R⁶, --COO--R⁷, --CONR⁹ R¹⁰, or ##EQU1## or --CH₂ CH(R¹¹)--[OCH₂ CH(R¹¹)]_(n) --R¹² ; R⁴ is hydrogen, lower alkyl or lower alkoxy; and

R⁵ is hydrogen, lower alkyl, lower alkoxy, hydroxy, --NHCO--R⁶, --NHCOO--R⁷ or --NHSO₂ --R⁷ ; in which

R⁶ is hydrogen; lower alkyl; lower alkyl substituted with halogen, hydroxy, lower alkoxy or aryl; aryl; lower alkylamino; or arylamino;

R⁷ is lower alkyl;

R⁸ is hydrogen or lower alkyl;

R⁹ individually is hydrogen or lower alkyl;

R¹⁰ individually is hydrogen or lower alkyl;

R⁹ and R¹⁰ in combination are pentamethylene or ethyleneoxyethylene;

R¹¹ is hydrogen or methyl;

n is 1, 2 or 3; and

R¹² is hydrogen or hydroxy; and

Each aryl is phenyl or phenyl substituted with lower alkyl, lower hydroxyalkyl, lower alkoxy, or halogen.

Our novel compounds produce unusual and unexpected bright, fast, blue to green shades on polyester, polyamide and cellulose ester fibers when applied thereto by conventional disperse dyeing techniques as compared to the corresponding benzothiazole dyes. Our azo compounds, in general, exhibit good dyeability as evidenced by levelness of dyeing, good build and fastness properties, such as light-fastness, wash fastness, gas fastness, resistance to sublimation and crock-fastness. This combination of properties, including the desirable blue shades produced, distinguishes our novel compounds from structurally-similar compounds known in the prior art.

The substituents represented by R¹ through R⁵ are well known in the art and can be derived from known intermediates according to published procedures. As used herein to describe an alkyl moiety, "lower" designates a carbon content of from one to about four. Preferably, R⁴ and R⁵ each is hydrogen and R³ is --(CH₂)_(m) --R¹³, --CH₂ CH(R¹¹)--R¹⁴, --CH₂ CH₂ CONR⁹ R¹⁰ or --CH₂ CH(R¹¹)--[OCH₂ CH(R¹¹)]_(n) --R¹² in which

m is 2 through 6;

R⁹ and R¹⁰ each is hydrogen or alkyl;

R¹¹ is hydrogen or methyl;

R¹³ is lower alkanoyl, lower hydroxyalkanoylamino, lower alkoxy-lower-alkanoylamino, lower alkoxycarbonylamino, lower alkylsulfonamido, 2-pyrrolidinono, or 5-methyl-2-pyrrolidinono;

R¹⁴ is hydroxy or lower alkoxycarbonyl;

R¹² is hydrogen or hydroxy; and

n is 1 or 2.

The azo compounds which are of particular value for producing blue shades on polyester, cellulose acetate, and, especially, polyamide fibers have the formula ##SPC2##

wherein

R¹ is hydrogen or a chlorine or bromine atom positioned at the 5- or 6-position; and

R³ is --CH₂ CH(R¹¹)--O--[CH₂ CH(R¹¹)--]_(m) R¹², --(CH₂)_(p) NHCOR⁸, --(CH₂)_(n) NHCOOR⁷, CH₂ CH(R¹¹)COOR⁷, --CH₂ CH₂ CONR⁹ R¹⁰, or (CH₂)_(p) --R¹³ ; in which

R⁷ is lower alkyl;

R⁸ is hydrogen or lower alkyl;

R⁹ and R¹⁰ each is hydrogen or lower alkyl;

R¹¹ is hydrogen or methyl;

R¹² is hydrogen or hydroxy;

m is 0, 1 or 2;

p is 2 or 3; and

R¹³ is 2-pyrrolidinono, or 5-methyl-2-pyrrolidinono.

Our azo compounds are prepared by diazotizing an amine having the formula ##SPC3##

and coupling the resulting diazonium salt with a naphthylamine coupler having the structure ##SPC4##

according to conventional procedures. The amine diazo precursors and the couplers are known compounds and/or can be prepared from available intermediates using known techniques. The published procedures, or minor variations thereof, employed in the synthesis of aniline couplers for azo dyes generally is applicable to the preparation of the couplers used in the synthesis of our novel compounds. The couplers also can be prepared by the Bucherer reaction utilizing available α-naphthols and amines.

Our novel azo compounds and their preparation are further described in the following examples:

EXAMPLE 1

A mixture of α-naphthol (28.8 g.), N,2-aminoethylpyrrolidin-2-one (76.8 g.), sodium bisulfite (20.8 g.) and water (170 ml.) is heated at 155°C. for 12 hours in an autoclave. The solid product is collected by filtration and recrystallized from 500 ml. of ethanol. There is obtained 37.4 g. of N,2(pyrrolidine-2-one)ethyl-α-naphthylamine which melts at 137°-139°C.

Anal. Calcd: C, 75.7; H, 7.2; N, 11.0. Found: C, 75.6; H, 7.2; N, 11.0.

EXAMPLE 2

To 5 ml. of concd. H₂ SO₄ is added 0.72 g. of NaNO₂ portionwise below 80°C. The solution is cooled and 10 ml. of 1:5 acid (1 part propionic:5 parts acetic acid) is added below 20°C. The mixture is cooled further and 3-amino-2,1-benzisothiazole (1.5 g.) is added, followed by 10 ml. of 1:5 acid, all at 0°-5°C. The diazonium, after stirring at 0°-5°C. for 1 hour, is added to an ice-cold solution of N-(2-acetamidoethyl)-α-naphthylamine (2.3 g.) in 15 ml. of 1:5 acid, below 10°C. The pH of the coupling mixture is adjusted to Congo Red with the addition of NH₄ OAc and coupling is allowed 45 minutes at 10°C. The coupling mixture is drowned in water and the azo product is collected by filtration, washed with water and air-dried. The azo compound obtained imparts blue shades to nylon fibers and exhibits good fastness properties.

EXAMPLE 3

3-Amino-5-chloro-2,1-benzisothiazole (1.84 g.) is dissolved in 25 ml. of 85% H₃ PO₄. A portion (0.72 g.) of NaNO₂ is added portionwise below 0°C. to the H₃ PO₄ solution. The diazonium, after stirring at 0°C. for 2.0 hours, is added to an ice-cold solution of N-(2-carbamoylethyl)-α-naphthylamine in 15 ml. of 1:5 acid below 10°C. The pH of the coupling mixture is adjusted to Congo Red with the addition of NH₄ OAc and coupling is allowed 1.0 hour at 10°C. The coupling mixture is drowned in water and the product is collected by filtration, washed with water and air-dried. The azo dye obtained imparts blue shades to nylon fibers.

The azo compounds set forth in the examples of the Table conform to formula (I) and are prepared according to the procedures described hereinabove. The color given for each azo compound refers to the shade it produces on nylon 66 fibers. Examples 4 and 5 of the Table designate the structures of the azo compounds prepared in the preceding examples. The positions of the R⁴ and R⁵ substituents have as their reference point the group --NHR³ and the azo group which are attached to the naphthalene nucleus at the 1- and 4-positions, respectively.

                                      Table                                        __________________________________________________________________________     Example No.                                                                           R.sup.1, R.sup.2                                                                            R.sup.3     R.sup.4, R.sup.5                                                                      Color                                   __________________________________________________________________________     4      H    --CH.sub.2 CH.sub.2 NHCOCH.sub.3                                                                   H      Blue                                    5      5-Cl --CH.sub.2 CH.sub.2 CONH.sub.2                                                                     H      Blue                                    6      H    --(CH.sub.2).sub.6 --NHCOCH.sub.3                                                                  H      Blue                                    7      H    --CH.sub.2 CH.sub.2 CH.sub.2 NHSO.sub.2 CH.sub.3                                                   H      Blue                                    8      H    --CH.sub.2 CH.sub.2 OH                                                                             H      Blue                                    9      H    --CH.sub.2 CH.sub.2 OC.sub.2 H.sub.4 OH                                                            H      Blue                                    10     H    --CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                             H      Blue                                    11     H    --CH.sub.2 CH.sub.2 NCH.sub.2 CH.sub.2 CH.sub.2 CO                                                 H      Blue                                    12     H    --CH.sub.2 CH.sub.2 OC.sub.2 H.sub.4 OC.sub.2 H.sub.5                                              H      Blue                                    13     H    --CH.sub.2 CH(OH)CH.sub.3                                                                          H      Blue                                    14     H    --CH.sub.2 CH(OH)CH.sub.2 OH                                                                       H      Blue                                    15     H    --CH.sub.2 CH.sub.2 CONH.sub.2                                                                     H      Blue                                    16     H    --CH.sub.2 CH.sub.2 CONHCH(CH.sub.3).sub.2                                                         H      Blue                                    17     H    --CH.sub.2 CH.sub.2 CON(C.sub.2 H.sub.5).sub.2                                                     H      Blue                                    18     H    --CH.sub.2 CH.sub.2 CONCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2                                        H      Blue                                    19     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCONHC.sub.2 H.sub.5                                                 H      Blue                                    20     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.2 OH                                                       H      Blue                                    21     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOOC.sub.2 H.sub.5                                                  H      Blue                                    22     H    --CH.sub.2 CH.sub.2 N(C.sub.2 H.sub.5)SO.sub.2 CH.sub.3                                            H      Blue                                    23     H    --CH.sub.2 CH.sub.2 COOC.sub.2 H.sub.5                                                             H      Blue                                    24     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCONHC.sub.6 H.sub.5                                                 H      Blue                                    25     H    --CH.sub.2 CH.sub.2 CH.sub.2 OC.sub.6 H.sub.5                                                      H      Blue                                    26     H    --CH.sub.2 CH.sub.2 CONCH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2                     CH.sub.2            H      Blue                                    27     H    --CH.sub.2 CH.sub.2 S--C=N--NH--CH=N                                                               H      Blue                                                O                                                                              ∥                                                         28     H    --CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 N(C.sub.2 H.sub.5)C--CH.                 sub.3               H      Blue                                    29     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.2 Cl                                                       H      Blue                                                O                                                                              ∥                                                         30     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCC.sub.6 H.sub.4 --p-OCH.sub.3                                      H      Blue                                                O                                                                              ∥                                                         31     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCCH.sub.2 CH.sub.2 OCH.sub.3                                        H      Blue                                    32     H    --CH.sub.2 CH.sub.2 S--C=N--N(C.sub.2 H.sub.5)--CH=N                                               H      Blue                                    33     H    --C.sub.6 H.sub.11  H      Blue                                    34     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.3                                                           H      Blue                                    35     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 OH                                                        H      Blue                                    36     H    --CH.sub.2 CH(OH)CH.sub.2 Cl                                                                       H      Blue                                    37     H    --CH.sub.2 CH(OH)CH.sub.2 OCH(CH.sub.3).sub.2                                                      H      Blue                                    38     H    --C.sub.6 H.sub.10 --p-CH.sub.3                                                                    H      Blue                                    39     H    --CH.sub.2 C.sub.6 H.sub.5                                                                         H      Blue                                    40     H    --CH.sub.2 C.sub.6 H.sub.4 --p-OC.sub.2 H.sub.4 OH                                                 H      Blue                                    41     H    --C.sub.6 H.sub.5   H      Blue                                    42     H    --C.sub.6 H.sub.4 --p-OC.sub.2 H.sub.4 OH                                                          H      Blue                                    43     H    --C.sub.6 H.sub.4 --p-OC.sub.2 H.sub.4 OCH.sub.3                                                   H      Blue                                    44     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOCH.sub.3                                              H      Blue                                    45     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.3                                                          7-CH.sub.3                                                                            Blue                                    46     H    --C.sub.6 H.sub.11  5-OH   Green                                   47     H    --CH.sub.2 CH.sub.2 CH.sub.2 CONH.sub.2                                                            H      Blue                                    48     H    --C.sub.6 H.sub.11  2-OCH.sub.3                                                                           Blue-Green                              49     H    --C.sub.6 H.sub.11  2-CH.sub.3                                                                            Blue                                    50     H    --C.sub.2 H.sub.4 COOCH.sub.3                                                                      5-NHCOCH.sub.3                                                                        Blue-Green                              51     H    --C.sub.6 H.sub.11  5-OCH.sub.3                                                                           Blue-Green                              52     5-Cl --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.2 CH.sub.3                                                 H      Blue                                    53     5-Cl --CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                             H      Blue                                    54     H    --CH.sub.2 CH.sub.2 CH.sub.2 NCH.sub.2 CH.sub.2 CH.sub.2                                           HO     Blue                                    55     Cl   --CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 OH                                                           H      Blue                                    56     Cl   --CH.sub.2 CH.sub.2 C.sub.6 H.sub.5                                                                H      Blue                                    57     Cl   --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH(CH.sub.3                                                       H.sub.2                                                                               Blue                                    58     Cl   --CH--CH.sub.2 C(CH.sub.3).sub.2 --CH.sub.2 --CH(CH.sub.3)CH.s                 ub.2                H      Blue                                    59     Cl   --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOOCH.sub.3                                             H      Blue                                    60     Cl   --CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2 CH.sub.3                                                     H      Blue                                                O                                                                              ∥                                                         61     Cl   --(CH.sub.2).sub.6 --NHCCH.sub.2 C.sub.6 H.sub.5                                                   H      Blue                                    62     Cl   --CH.sub.2 CH.sub.2 CN                                                                             H      Blue                                    63     5-Cl --C.sub.6 H.sub.4 --p-C.sub.2 H.sub.4 OH                                                           H      Blue                                    64     5-Cl --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.3                                                          5-OH   Green                                   65     5-Cl --CH.sub.2 CH.sub.2 COOC.sub.2 H.sub.4 OCH.sub.3                                                   H      Blue                                    66     5-Cl --CH.sub.2 CH.sub.2 COOCH.sub.2 C.sub.6 H.sub.5                                                    H      Blue                                    67     5-Cl --C(CH.sub.3).sub.2 CH.sub.2 OH                                                                    H      Blue                                    68     5-Br --CH.sub.2 CH.sub.2 CH.sub.2 NHCOC.sub.2 H.sub.5                                                   H      Blue                                    69     5-Br --CH.sub.2 CH.sub.2 OC.sub.2 H.sub.4 OH                                                            H      Blue                                    70     5-Br --CH.sub.2 CH.sub.2 OC.sub.2 H.sub. 4 CN                                                           H      Blue                                    71     H    --(CH.sub.2).sub.3 --NCH.sub.2 CH.sub.2 CH.sub.2 CO                                                H      Blue                                    72     6-CH.sub.3                                                                          --(CH.sub.2).sub.3 --NCH.sub.2 CH.sub.2 CH.sub.2 CO                                                H      Blue                                    73     6-CH.sub.3                                                                          --CH.sub.2 CH.sub.2 CH.sub.2 O--m-C.sub.4 H.sub.9                                                  H      Blue                                    74     6-OCH.sub.3                                                                         --CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                             H      Blue                                    75     6-OCH.sub.3                                                                         --CH.sub.2 CH.sub.2 CONH.sub.2                                                                     H      Blue                                    76     5-OCH.sub.3                                                                         --CH.sub.2 CH.sub.2 NHCOCH.sub.3                                                                   H      Blue                                    77     5-CH.sub.3                                                                          --(CH.sub.2).sub.6 --NHCOCH.sub.2 CH.sub.3                                                         H      Blue                                    78     5-CH.sub.3                                                                          C.sub.6 H.sub.11    H      Blue                                    79     H    --C.sub.2 H.sub.4 COOCH.sub.3                                                                      2-OC.sub.2 H.sub.5                                                                    Blue-Green                              80     H    --C.sub.2 H.sub.4 COOCH.sub.3                                                                      2-CH.sub.3                                                                            Blue                                    81     H    --CH.sub.2 C.sub.6 H.sub.11                                                                        H      Blue                                    82     H                        H      Blue                                    83     H    --CH.sub.2 CH.sub.2 NCH(CH.sub.3)CH.sub.2 CH.sub.2 CO                                              H      Blue                                    84     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.2 Cl                                                       H      Blue                                    85     H    --CH.sub.2 CH.sub.2 CH.sub.2 NHCOCH.sub.2 CH.sub.2 OC.sub.2                    H.sub.5             H      Blue                                    86     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOH                                                     H      Blue                                    87     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOCH.sub.2                                              Hl     Blue                                    88     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOCH.sub.2                                              HH     Blue                                    89     5-Cl --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOC.sub.6 H.sub.5                                       H      Blue                                    90     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCONHC.sub.2                         H.sub.5             H      Blue                                    91     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCONHC.sub.6                         H.sub.5             H      Blue                                    92     H    --C.sub.2 H.sub.4 OC.sub.2 H.sub.4 OH                                                              H      Blue                                    93     H    --C.sub.2 H.sub.4 OC.sub.2 H.sub.4 OC.sub.2 H.sub.5                                                H      Blue                                    94     H    --C.sub.2 H.sub.4 OC.sub.2 H.sub.5                                                                 H      Blue                                    95     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 NHCOCH.sub.2 C.sub.6                  H.sub.5             H      Blue                                    96     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub. 2 NHSO.sub.2 C.sub.2                   H.sub.5             H      Blue                                    97     H    --CH.sub.2 C.sub.6 H.sub.10 --p-CH.sub.2 N(C.sub.2 H.sub.5)SO.                 sub.2 CH.sub.3      H      Blue                                    98     H    --CH.sub.2 CH.sub.2 CH.sub.2 N(C.sub.2 H.sub.5)COCH.sub.2                                          HH     Blue                                    99     H    --CH.sub.2 CH.sub.2 CH.sub.2 N(C.sub.2 H.sub.5)CONHC.sub.6                     H.sub.5             H      Blue                                    100    5-Cl --C.sub.2 H.sub.4 OCOCH.sub.3                                                                      H      Blue                                    101    5-Cl --C.sub.2 H.sub.4 OCOCH.sub.2 OH                                                                   H      Blue                                    102    5-Cl --C.sub.2 H.sub.4 OCOCH.sub.2 Cl                                                                   H      Blue                                    103    5-Cl --C.sub.2 H.sub.4 OCOC.sub.6 H.sub.5                                                               H      Blue                                    104    H    --CH.sub.2 CH.sub.2 CH.sub.2 OCONHC.sub.2 H.sub.5                                                  H      Blue                                    105    H    --CH.sub.2 CH.sub.2 CH.sub.2 OCONHC.sub.6 H.sub.5                                                  H      Blue                                    __________________________________________________________________________

The novel azo compounds can be applied to nylon, polyester and cellulose acetate fibers according to known disperse dyeing techniques. Various dispersing and wetting agents can be employed in the dispersion of the finely divided dye compound in an essentially aqueous dyebath. Procedures by which the compounds of the invention can be applied to nylon and polyester textile materials are described in U.S. Pat. Nos. 2,880,050; 2,757,064; 2,782,187; 3,100,134 and 3,320,021. The following examples illustrate methods for applying the novel compounds to polyamide fibers and polyester fibers, respectively.

EXAMPLE 106

The azo compound (50.0 mg.) of Example 2 is dispersed in 5 cc. of 2-methoxyethanol. A small amount (3-5 cc.) of a 3% sodium lignin sulfonate solution is added, with stirring, and then the volume of the bath is brought to 150 cc. with water. A 5.0 g. textile fabric made of nylon 66 fibers is placed in the bath which is then slowly brought to the boil. The dyeing is carried out at the boil for 1 hour with occasional stirring. The dyed fabric is then removed from the dyebath, rinsed with water, and dried in an oven at 250°F. The fabric is dyed a bright shade of blue exhibiting excellent fastness properties when tested in accordance with the procedures described in the Technical Manual of the American Association of Textile Chemists and Colorists (AATCC), 1968 edition.

EXAMPLE 107

The azo compound of Example 3 (0.1 g.) is dissolved in 10 cc. of 2-methoxyethanol. A small amount (3-5 cc.) of a 3% sodium lignin sulfonate aqueous solution is added, with stirring, and then the volume of the bath is brought to 300 cc. with water. Three cc. of a carrier (o-phenylphenol) is added to the bath and 10 g. of a textile fabric made of poly(ethylene terephthalate) fibers is placed in the bath and worked 10 minutes without heat. The dyeing is carried out at the boil for 1 hour. The dyed fabric is removed from the dyebath and scoured for 20 minutes at 80°C. in a solution containing 1 g./liter neutral soap and 1 g./liter sodium carbonate. The fabric is then rinsed, dried in an oven at 250°F. and heat set (for removal of residual carrier) for 5 minutes at 350°C. The polyester fabric is dyed a bright blue shade which exhibits excellent fastness to light and resistance to sublimation when tested according to conventional AATCC procedures.

The compounds of the invention can also be applied to polyester textile materials by the heat fixation technique described in U.S. Pat. No. 2,663,612 and in the American Dyestuff Reporter, 42, 1 (1953).

As used herein, "nylon textile materials" means fibers, yarns and fabrics having a basis of a synthetic linear polyamide such as nylon 66 (polyhexamethylene adipamide) manufactured by the polymerization of adipic acid and hexamethylenediamine, nylon 6 (polycaprolactam) prepared from epsilon-aminocaproic acid lactam (caprolactam), and nylon 8. A detailed description of the synthetic polyamide materials which are dyed bright fast shades by the compounds of the invention is set forth in U.S. Pat. No. 3,100,134.

Polymeric linear polyester materials of the terephthalate sold under the trademarks "Kodel", "Dacron" and "Terylene" are illustrative of the linear aromatic polyester textile materials that can be dyed with the compounds of our invention. Examples of linear polyester textile materials that can be dyed with the compounds of the invention are those prepared from ethylene glycol and dimethylterephthalate or from cyclohexanedimethanol and dimethylterephthalate. Polyesters prepared from cyclohexanedimethanol and dimethylterephthalate are more particularly described in U.S. Pat. No. 2,901,466. Poly(ethylene terephthalate) polyester fibers are described, for example, in U.S. Pat. No. 2,465,319. The polymeric linear polyester materials disclosed in U.S. Pat. Nos. 2,945,010; 2,957,745 and 2,989,363, for example, can be dyed. The linear aromatic polyester materials specifically named have a melting point of at least 200°C. The poly(ethylene terephthalate) fibers which are dyed with the compounds of the invention are manufactured from a melt of a polymer having an inherent viscosity of at least 0.35 and preferably, about 0.6. The inherent viscosity of the poly(1,4-cyclohexylenedimethylene terephthalate) polymer is also at least 0.35. These inherent viscosities are measured at 25°C. using 0.25 g. polymer per 100 ml. of a solvent consisting of 60% phenol and 40% tetrachloroethane. The polyester fabrics, yarns, fibers and filaments that are dyed with the novel azo compounds can also contain minor amounts of other additives such as brighteners, pigments, delusterants, inhibitors, stabilizers, etc.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. 

We claim:
 1. A compound having the formula ##SPC5##wherein R¹ and R² each is hydrogen, lower alkyl, lower alkoxy, chlorine or bromine; R³ is cyclohexyl; lower alkyl cyclohexyl; aryl; alkyl of one to about six carbon atoms substituted with hydroxy, lower alkoxy, lower cyanoalkoxy, lower hydroxyalkoxy, cyano, halogen, aryl, aryloxy, cyclohexyl, lower alkylcyclohexyl, hydroxymethylcyclohexyl, R⁶ --CONHCH₂ -cyclohexyl, R⁷ OOCNHCH₂ -cyclohexyl, R⁷ SO₂ N(R⁸)CH₂ -cyclohexyl, pyrrolidinono, lower alkylpyrrolidinono, phthalimidino, --N(R⁸)CO--R⁶, --NHCOO--R⁷, --N(R⁸)SO₂ R⁷, --OOC--R⁶, --COO--R⁷, --CONR⁹ R¹⁰, ##EQU2## or --CH₂ CH(R¹¹)--[OCH₂ CH(R¹¹)]_(n) --R¹² ; R⁴ is hydrogen, lower alkyl or lower alkoxy; and R⁵ is hydrogen, lower alkyl, lower alkoxy, hydroxy, --NHCO--R⁶, --NHCOO--R⁷ or --NHSO₂ --R⁷, in which R⁶ is hydrogen; lower alkyl; lower alkyl substituted with halogen, hydroxy, lower alkoxy or aryl; aryl; lower alkylamino; or arylamino; R⁷ is lower alkyl; R⁸ is hydrogen or lower alkyl; R⁹ individually is hydrogen or lower alkyl; R¹⁰ individually is hydrogen or lower alkyl; R⁹ and R¹⁰ in combination are pentamethylene or ethyleneoxyethylene; R¹¹ is hydrogen or methyl; n is 1, 2 or 3; and R¹² is hydrogen or hydroxy; and each aryl as well as the aryl moiety of each aryloxy and arylamino is phenyl or phenyl substituted with lower alkyl, lower hydroxyalkyl, lower alkoxy, or chlorine.
 2. A compound according to claim 1 whereinR², r⁴ and R⁵ are hydrogen; and R³ is --(CH₂)_(m) --R¹³, --CH₂ CH(R¹¹)--R¹⁴, --CH₂ CH₂ CONR⁹ R¹⁰ or --CH₂ CH(R¹¹)--[OCH₂ CH(R¹¹)]_(n) --R¹⁵ in which m is 2 through 6; R⁹ and R¹⁰ each is hydrogen or alkyl; R¹¹ is hydrogen or methyl; R¹³ is lower alkanoylamino, lower hydroxyalkanoylamino, lower alkoxy-lower-alkanoylamino, lower phenylalkanoylamino, lower alkoxycarbonylamino, lower alkylsulfonamido, 2-pyrrolidinono or 5-methyl-2-pyrrolidinono; R¹⁴ is hydroxy or lower alkoxycarbonyl; R¹⁵ is hydrogen or hydroxy; and n is 1 or
 2. 3. A compound according to claim 1 having the formula ##SPC6##wherein R¹ is hydrogen or a chlorine or bromine atom positioned at the 5- or 6-position; and R³ is --CH₂ CH(R¹¹)--O--[CH₂ CH(R¹¹)--]_(m) R¹², --(CH₂)_(p) NHCOR⁸, --(CH₂)_(n) NHCOOR⁷, CH₂ CH(R¹¹)COOR⁷, --CH₂ CH₂ CONR⁹ R¹⁰, or (CH₂)_(p) --R¹³ ; in which R⁷ is lower alkyl; R⁸ is hydrogen or lower alkyl; R⁹ and R¹⁰ each is hydrogen or lower alkyl; R¹¹ is hydrogen or methyl; R¹² is hydrogen or hydroxy; m is 0, 1 or 2; p is 2 or 3; and R¹³ is 2-pyrrolidinono or 5-methyl-2-pyrrolidinono.
 4. A compound according to claim 1 having the formula ##SPC7##
 5. A compound according to claim 1 having the formula ##SPC8##
 6. A compound according to claim 1 having the formula ##SPC9## 